Just found out I’m pregnant

I feel so stupid. I’ve been having sex with my ex and today I found out that I’m pregnant. I don’t know what to do. When we was together, I found out that he was still with his baby mama and another woman while we was together. A few weeks earlier he asked me to come over so we could talk and I did. We ended up having sex. Then we started back having sex every other day. I feel so stupid. I already have two children by another man who doesn’t help me. Even though my ex is a great person except when it comes down to relationships, I can’t put myself through this. It makes me angry to know that he’s comfortable having baby mamas and no commitment. I find myself getting jealous of his other baby mama. I feel like I hate him. I don’t know what to do. I need help